JP2005266372A - Manufacturing method of optical master disk, manufacturing method of optical disk, and exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance exposure velocity per unit time by heightening utilization efficiency of a light source, in manufacture of an optical master disk. <P>SOLUTION: In an exposure device for an optical master disk, a diffraction optical element 2 is provided between a laser beam 1 and an object lens 3 and a means for making a luminous flux 6 formed by the diffraction optical element incident on the object lens 3. The diffraction optical element 2 is formed by using e.g. quartz glass as a material so as to be flat only within a pupil and extremely low luminous outside the pupil in a pupil position 5. Since the luminous flux 6 formed in the pupil position 5 hardly has the luminous flux outside the pupil, the light source can be effectively utilized and a laser profile can be made acute. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical disk manufacturing technique, and more particularly to a technique that is effective when applied to an exposure technique in a lithography process in a mastering manufacturing process for manufacturing a read-only optical disk.

  FIG. 13 shows the structure of a read-only medium such as a CD-ROM (Compact Disc-Read Only Memory) and a DVD (Digital Versatile Disc) -ROM and how it is read.

  As shown in the figure, the optical disk is composed of a reflective layer 52, a protective layer 53, and an adhesive layer 54 on a disk substrate 51. The reading laser beam 50 irradiated from below the disk substrate 51 is reflected by the pits 55 that are irregularities on the disk substrate to read information.

  To manufacture an optical disk, an optical disk master called a stamper is first prepared, and the disk substrate 51 is transferred to the disk by injection molding.

  When forming a pit pattern on an optical disc master, for example, a laser beam type optical disc exposure apparatus is widely used. In this laser beam type optical disk master exposure apparatus, the recording density can be improved by miniaturizing the spots exposed by the photoresist.

  For example, in Patent Document 1, two focused laser beams are used, and irradiation is performed by shifting the position in the front, rear, left, and right directions, and control is performed so that the overlapping area becomes a resist photosensitive area. In this configuration, pits finer than the light condensing spot can be formed (see Patent Document 1).

  In an optical disc, the drawing density in the exposure process of drawing a pit pattern on a photoresist determines the recording capacity of the optical disc. For example, a Blu-ray standard 12 cm disk 25 GB medium requires a minimum pit diameter of about 0.149 μm.

  As a method of performing drawing at a density of 25 Gbytes or more, a method of drawing by an electron beam (EB: Electron Beam) (see Non-Patent Document 1), a method of condensing an ultraviolet laser, and the like have been proposed.

In the drawing by the electron beam method, high-density drawing with 200 Gbytes is possible, but there are problems that the drawing speed is slow and the drawing apparatus is expensive. The method of condensing the ultraviolet laser has many common parts with the current DVD mastering apparatus, and has an advantage that it can be realized as a low-cost and high-speed exposure drawing apparatus.
Japanese Patent Laid-Open No. 06-274944 "Nikkei Electronics", published by Nikkei BP, May 12, 2003, P124, P125

  However, the present inventors have found that there are the following problems in the optical disk master manufacturing technology as described above.

  In order to form fine pits with a single laser beam, it is essential to make the focused spot minute. In semiconductor exposure, a technique for reducing a beam spot using super-resolution in order to form a pattern below the resolution limit of a lens is known.

  An example thereof will be described with reference to FIGS. FIG. 14 shows an example of a conventional laser beam condensing optical system when super-resolution is not used.

  The laser light 56 from the laser light source has a Gaussian distribution in which the output near the center is high and decreases as it approaches the periphery. The laser beam 56 is collected by an objective lens 57 and forms an image as a spot 59 on a resist-coated substrate 58. The beam profile 70 at the pupil position 60 in the objective lens 57 is equivalent to the laser beam 56.

  15 and 16 are examples using super-resolution.

  FIG. 15 shows a configuration in which laser light 56 that is incident light on the objective lens 57 is enlarged by a beam expander 80 so as to have a beam profile 81 at a pupil position 60, and only a flat region near the beam center is condensed. It is a thing. By doing so, it is known that the beam spot 82 at the focal position has a smaller spot diameter than the spot 59 in FIG.

  Similarly, as shown in FIG. 16, in addition to FIG. 15, the beam spot 84 at the focal position can also be obtained as a spot 59 by adding a mask 83 in the form of a ring to the pupil position 60 of the objective lens to form a ring illumination. Smaller spot diameter.

  However, in these methods, since only a part of the laser beam is used, there is a problem that the amount of light after condensing is reduced and the utilization efficiency of the light source is lowered. Further, since the exposure speed per unit time is lowered, the throughput is also a problem.

  An object of the present invention is to provide a technique for manufacturing an optical disc master capable of greatly improving the exposure speed per unit time by increasing the utilization efficiency of a light source.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  The method for producing an optical disc master according to the present invention uses a diffractive optical element in an optical path when a laser beam is used as an exposure light source and a recording beam spot is formed by a condenser lens in an exposure process for recording reproduction information on the optical disc master. An element is used to sharpen the shape of the recording beam spot and reduce the spot diameter.

  Also, the optical disk master manufacturing method according to the present invention provides a diffractive optical element in the optical path when a laser beam is used as an exposure light source and a recording beam spot is formed by a condenser lens in an exposure process for recording reproduction information on the optical disk master. The element is used to improve the center intensity of the recording beam spot.

  Moreover, the outline | summary of the other invention of this application is shown briefly.

  The present invention is an exposure apparatus for performing exposure for recording reproduction information on an optical disk master, and is provided with an exposure light source for irradiating a laser beam, and a laser beam emitted from the exposure light source provided in an optical path of the exposure light source. A diffractive optical element that forms a light beam having a desired shape and a condensing lens that forms the light beam formed by the diffractive optical element into the shape of a recording beam spot. The diffractive optical element is irradiated from an exposure light source. The laser beam is formed in a shape that sharpens the recording beam spot formed by the condenser lens and reduces the spot diameter.

  The present invention also relates to an exposure apparatus for performing exposure for recording reproduction information on an optical disc master, an exposure light source for irradiating a laser beam, and a laser irradiated in the optical path of the exposure light source. A diffractive optical element that forms light into a light beam having a desired shape and a condensing lens that forms the light beam formed by the diffractive optical element into the shape of a recording beam spot. The diffractive optical element is irradiated from an exposure light source. The laser beam thus formed is formed into a shape in which the central intensity of the recording beam spot formed by the condenser lens is improved.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  (1) Since an exposure pattern with high resolution performance can be generated, a highly accurate optical disc master can be manufactured.

  (2) Further, since the utilization efficiency of the exposure light source can be increased, the exposure speed can be improved.

  (3) Furthermore, according to the above (1) and (2), it becomes possible to improve the throughput in the production of the optical disc master, and the production cost can be greatly reduced.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

(Embodiment 1)
FIG. 1 is an explanatory diagram showing a configuration example of an optical disc master exposure apparatus according to Embodiment 1 of the present invention, FIG. 2 is an explanatory diagram of an optical system in the optical disc master exposure apparatus of FIG. 1, and FIG. FIG. 4 is a comparison of the laser profile studied by the present inventor with the laser profile in the optical disc master exposure apparatus of FIG. 1, and FIG. FIG. 6 is a cross-sectional view of the diffractive optical element of FIG. 5, and FIG. 7 is a diffraction pattern of the diffractive optical element provided in the optical disc master exposure apparatus of FIG. 8 is an explanatory view showing another example of the optical element, FIG. 8 is an explanatory view of a ring-shaped light beam formed by the diffractive optical element of FIG. 7, and FIG. 9 is an optical disc for reproduction using the optical disc master exposure apparatus of FIG. Example of manufacturing method To illustration, FIG. 10 is an explanatory view of a manufacturing process of the optical disc master used in the manufacture of reproducing optical disk shown in FIG.

  In this embodiment, as shown in FIG. 1, the optical disc master exposure apparatus includes a turntable device 31, a turntable control unit 304, a recording data processing unit 305, an optical head control system 303, an exposure device optical system 30, and recording data. The storage unit 306 is configured.

  The optical device optical unit 30 includes a recording laser light source 301, an autofocus laser light source 302, a half mirror 38, a focus position detector 39, a reflection mirror 37, a diffractive optical element 2, an autofocus dichroic mirror 35, and an objective lens ( Condensing lens) 3.

  The resist master disk 32 is set on the turntable device 31. In the optical device optical system 30, the laser light from the recording laser light source 301 is reflected by the reflection mirror 37, and then shaped into a desired shape by the diffractive optical element 2, and then passed through the autofocus dichroic mirror 35. Then, it is made incident on the objective lens 3 to irradiate the recording beam spot 7 on the disk master 32.

  Further, as an autofocus mechanism, a laser beam from an autofocus laser light source 302 having a wavelength different from that of the recording laser light source 301 is irradiated onto the sample surface through the half mirror 38 by the autofocus dichroic mirror 35 and the objective lens 3. Then, the reflected light is reflected again by the half mirror 38 via the objective lens 3 and the autofocus dichroic mirror 35, and detected by the focus position detector 39.

  The focus position detector 39 is adjusted in advance to the reflection position of the autofocus laser at the in-focus position, and is configured to output a signal corresponding to the focus shift. The turntable device 31 adjusts the height of the disc master 32 based on the signal detected by the focus position detector 39, and operates so that the pit exposure spot by the exposure device optical system 30 is always at the in-focus position.

  On the other hand, the data stored in the optical disk stored in the recording data storage unit 306 is converted into a pit pattern by the recording data processing unit 305, and the turntable control unit 304 and the exposure apparatus optical system 30 move the data to a predetermined recording position. It is recorded as a pit pattern, and the exposure to the disc master 32 is performed.

  The manner in which the recording beam spot 7 is generated by the optical system of the optical disk master exposure apparatus will be described in detail with reference to FIG.

  The laser beam 1 from the recording laser light source 301 is incident on the diffractive optical element 2. At this time, the diffractive optical element 2 is shaped so that the pupil position 5 of the objective lens 3 is flat only in the pupil and extremely low brightness outside the pupil. The shaped light beam 6 is condensed and irradiated as a recording beam spot 7 onto the recording resist 24 of the disk master 32.

  A light beam 6 formed on the diffractive optical element 2 is shown in FIG.

  In FIG. 3, the distribution 40 in the vertical direction on the optical axis of the light beam 6 is shown above, and the distribution 41 of the cross section on the optical axis of the light beam 6 is shown below. It is the same as the pupil diameter.

  With such a configuration, the laser profile can be sharpened. Further, by using a deep ultraviolet laser having a wavelength of approximately 300 nm or less as the wavelength of the recording laser light source 301, an existing light source can be used as the recording laser light source, and the cost of the optical disc master exposure apparatus can be reduced. it can.

  FIG. 4 is an explanatory diagram showing an example of the laser profile 20 examined by the present inventors and the laser profile 22 in the present embodiment.

  In this way, by forming the light beam 6 by the diffractive optical element 2, what was conventionally the laser profile 20 on the recording surface becomes a sharp laser profile 22 near the center.

  At this time, the spot diameter for recording when the required photosensitive reaction intensity of the resist is 25 or more can be made as small as the diameter 21 to the diameter 23. Further, since the shaped light beam 6 at the pupil position 5 has almost no light beam outside the pupil, the light source can be effectively used, and the utilization efficiency is hardly lowered.

  The shape of the diffractive optical element 2 is shown in FIGS. FIG. 5 shows a distribution 100 on the main surface of the diffractive optical element 2, and FIG. 6 shows a cross section of the diffractive optical element 2.

  The diffractive optical element 2 is made of, for example, quartz glass, and has a distribution that changes the phase of incident light for each minute area as indicated by a distribution 100. Moreover, as shown in FIG. 6, it forms by the level | step differences 102 and 103 which produce a phase difference. The level difference is about several μm in both the horizontal and depth directions.

  FIG. 7 is an explanatory view showing another example of the recording beam spot 7 formed by using the diffractive optical element 2a.

  As shown in FIG. 7, in the optical disc master exposure apparatus, the diffractive optical element 2a has a different shape from the diffractive optical element 2 (FIG. 1).

  The laser beam 1 from the laser light source is incident on the diffractive optical element 2a, and the annular light beam 43 is formed in the pupil at the pupil position 5 of the objective lens 3. The formed annular light beam 43 is condensed and irradiated onto the recording resist 24 as a recording beam spot 7.

  FIG. 8 shows an annular light beam 43 formed by the diffractive optical element 2a.

  In FIG. 8, the distribution 42 in the direction perpendicular to the optical axis of the annular light beam 43 is shown in the upper part, and the distribution 44 in the cross-sectional direction of the optical axis in the annular light beam 43 is shown in the lower part.

  The distribution 44 is a distribution having no light beam outside the pupil diameter of the objective lens 3. By adopting such a configuration, as shown in FIG. 4, a laser profile 22 that is sharp in the vicinity of the center can be obtained.

  FIG. 9 is an explanatory view showing an example of a method of manufacturing a reproduction optical disk (DVD) using an optical disk master exposure apparatus.

  First, based on the data stored in the recording data storage unit 306, the optical disk master exposure apparatus exposes desired master data to a disk master (glass substrate) coated with a recording resist. After developing the exposed resist master, a stamper is manufactured by nickel plating.

  Thereafter, a disc material such as plastic is injection-molded onto the stamper, and the pattern is transferred to produce an optical disc such as a reproduction-only DVD.

  As described above, by using the optical disc master exposure apparatus, it is possible to produce a reproduction optical disc such as a large-capacity DVD at a low cost.

  Next, a manufacturing process of an optical disc master used for manufacturing the reproducing optical disc shown in FIG. 9 will be described with reference to FIG.

  First, as shown in FIG. 10B, the recording resist 24 is applied on the glass master 61 shown in FIG. Subsequently, as shown in FIG. 10C, a pit pattern 63 to be transferred by irradiating the recording beam spot 7 onto the main surface of the glass master 61 coated with the recording resist 24 using an optical disk master exposure apparatus is transferred. Drawing is performed, and the recording resist 24 is exposed.

  Then, development processing is performed, and a pit pattern 63 is formed on the main surface of the glass master 61 as shown in FIG.

  Thereafter, as shown in FIG. 10 (e), the main surface of the glass master 61 on which the pit pattern 63 is formed is subjected to nickel plating, and then the nickel plating is peeled off, as shown in FIG. 10 (f). A stamper 64 is produced.

  Then, as shown in FIGS. 10G and 10H, using the stamper 64, the reproducing disk 65 is transferred and peeled by the manufacturing method shown in FIG. .

  Thus, according to the first embodiment, a high-performance optical disc master can be formed in a short time by using the diffractive optical element 2 that sharpens the laser profile.

(Embodiment 2)
FIG. 11 is an explanatory diagram showing a configuration example of the optical system in the optical disc master exposure apparatus according to the second embodiment of the present invention.

  In the second embodiment, FIG. 11 is an explanatory diagram of an optical system in an optical disk master exposure apparatus combined with an immersion lens system. Among the optical systems, the laser beam 1, the diffractive optical element 2, the objective lens 3, the pupil position 5, the light beam 6, and the recording beam spot 7 in the optical system are the same as those in the first embodiment, and a description thereof will be omitted. To do.

  Pure water in the pure water tank 201 is discharged between the objective lens 3 and the substrate 4 from the discharger 202 to form a pure water region 200. On the other hand, the water absorber 203 collects excess pure water in the pure water tank 201.

  Since the numerical aperture (NA) of the objective lens 3 used for mastering the optical disc is generally about 0.9, and the distance (working distance) between the objective lens and the substrate 4 is about several hundred μm, the pure water region 200 is an objective lens. Only a small area around the periphery is sufficient.

  By adopting such a configuration, it is possible to use a water refractive index of 1.44, which is larger than the refractive index of air 1.

  In general, the resolution of an optical disc exposure apparatus becomes higher as the wavelength of the laser light source is shorter and as the numerical aperture (NA) of the objective lens is larger. Since NA is proportional to the refractive index of the medium, a resolution 1.44 times higher than that of air can be obtained.

  The medium to be supplied need not be limited to pure water, and may be any medium that has a refractive index greater than the refractive index 1 of air and does not affect the objective lens and the substrate 4.

  Even in this case, a deep ultraviolet laser having a wavelength of approximately 300 nm or less is used for the recording laser light source 301. As a result, an existing light source can be used as the recording laser light source, and the cost of the optical disk master exposure apparatus can be reduced.

  Thereby, in the second embodiment, an exposure pattern with a higher resolution can be formed, so that a higher-performance optical disc master can be formed in a short time.

(Embodiment 3)
FIG. 12 is an explanatory diagram showing a configuration example of the optical system in the optical disc master exposure apparatus according to the third embodiment of the present invention.

  In the third embodiment, FIG. 12 shows another configuration of the autofocus portion of the exposure apparatus optical system 30 portion in the optical disk master exposure apparatus of the first embodiment.

  As shown in the figure, the laser light from the recording laser light source 301 is condensed as a recording beam spot 7 on the substrate 4 coated with resist by the reflecting mirror 37, the diffractive optical element 2, and the objective lens 3.

  Further, the laser light from the autofocus laser 302 having a wavelength different from that of the recording laser light source 301 is reflected on the substrate 4 via the reflection mirror 310 and is arranged at a position symmetrical to the reflection mirror 310. 311 is incident.

  In the optical position detection sensor 311, since the position of the incident light changes according to the height of the substrate 4, it is possible to detect the height displacement of the substrate 4, and therefore the exposure apparatus optical system 30 from the output value. Functions as an autofocus mechanism.

  Also in the third embodiment, a deep ultraviolet laser having a wavelength of approximately 300 nm or less is used as a recording laser light source. Thereby, the cost of the optical disk master exposure apparatus can be reduced.

  Thereby, also in the third embodiment, a high-performance optical disc master can be formed in a short time.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  The optical disk master manufacturing technology of the present invention is suitable for high-precision exposure technology in the optical disk master manufacturing process.

It is explanatory drawing which shows the structural example of the optical disk original recording exposure apparatus by Embodiment 1 of this invention. It is explanatory drawing of the optical system in the optical disk original recording exposure apparatus of FIG. FIG. 2 is a distribution diagram of luminous flux formed at the objective lens pupil position of the optical disc master exposure apparatus of FIG. 1. It is a comparison figure of the laser profile which this inventor examined, and the laser profile in the optical disk original recording exposure apparatus of FIG. FIG. 2 is a light flux distribution diagram of a diffractive optical element provided in the optical disc master exposure apparatus of FIG. 1. It is sectional drawing of the diffractive optical element of FIG. It is explanatory drawing which shows the other example of the diffractive optical element provided in the optical disk original disc exposure apparatus of FIG. It is explanatory drawing of the ring-shaped light beam shape | molded by the diffractive optical element of FIG. It is explanatory drawing which shows an example of the manufacturing method of the optical disk for reproduction | regeneration using the optical disk original disc exposure apparatus of FIG. It is explanatory drawing of the manufacturing process of the optical disk original disk used for manufacture of the optical disk for reproduction | regeneration shown in FIG. It is explanatory drawing which shows the structural example of the optical system in the optical disk original recording exposure apparatus by Embodiment 2 of this invention. It is explanatory drawing which shows the structural example of the optical system in the optical disk original recording exposure apparatus by Embodiment 3 of this invention. It is explanatory drawing which shows the structure of the optical disk read-only medium which this inventor examined, and the mode of reading. It is explanatory drawing which shows the structure of the condensing optical system which does not use the conventional super-resolution which this inventor examined in the optical disk master exposure apparatus. It is explanatory drawing which shows an example of a structure of the condensing optical system at the time of using the conventional super-resolution which this inventor examined in the optical disk master exposure apparatus. It is explanatory drawing which shows the other example of a structure of the condensing optical system at the time of using the conventional super-resolution which this inventor examined in the optical disk original recording exposure apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Laser beam, 2 ... Diffraction optical element, 2a ... Diffraction optical element, 3 ... Objective lens (condensing lens), 4 ... Substrate, 5 ... Pupil position, 6 ... Light beam, 7 ... Recording beam spot, 20 ... Laser Profile, 21 ... beam spot diameter, 22 ... beam spot profile, 23 ... beam spot diameter, 24 ... recording resist 25 ... photosensitive intensity threshold, 30 ... exposure device optical system, 31 ... turntable device, 32 ... disk master, 34 ... objective lens, 35 ... dichroic mirror for autofocus, 36 ... beam diameter adjusting mechanism, 37 ... reflection mirror, 38 ... half mirror, 39 ... focus position detector, 301 ... laser light source for recording, 302 ... laser for autofocus Light source, 303 ... optical head control system, 304 ... turntable control unit, 305 ... recording data processing unit, 306 ... recording data storage unit, 40 41, 42 ... distribution, 43 ... annular light flux, 44 ... distribution, 50 ... reading laser light, 51 ... disk substrate, 52 ... reflective layer, 53 ... protective layer, 54 ... adhesive layer, 55 ... pit, 56 ... laser light 57 ... objective lens, 58 ... substrate, 59 ... spot, 60 ... pupil position, 61 ... glass master, 63 ... pit pattern, 64 ... stamper, 65 ... playback disc, 70 ... beam profile, 80 ... beam expander, DESCRIPTION OF SYMBOLS 81 ... Beam profile, 82 ... Beam spot, 83 ... Ring body mask, 84 ... Beam spot, 100 ... Distribution, 102, 103 ... Step, 200 ... Pure water area, 201 ... Pure water tank, 202 ... Ejector, 203 ... Absorber, 301... Recording laser, 302... Autofocus laser, 310... Reflection mirror, 311.

Claims (13)

A method of manufacturing an optical disc master,
In the exposure process for recording reproduction information on the optical disc master, when a laser beam is used as an exposure light source and a recording beam spot is formed by a condenser lens, a recording beam spot is used using a diffractive optical element in the optical path. A method of manufacturing an optical disc master, wherein the shape of the optical disc is sharpened and the spot diameter is reduced. A method of manufacturing an optical disc master,
In the exposure step of recording reproduction information on the optical disc master, when a laser beam is used as an exposure light source and a recording beam spot is formed by a condensing lens, a diffractive optical element is used in the optical path, and the center of the recording beam spot is A method for manufacturing an optical disc master, characterized by improving strength. In the manufacturing method of the optical disc master according to claim 1 or 2,
An optical disk master manufacturing method, wherein ultraviolet light having a wavelength of 300 nm or less is used for laser light of the exposure light source, and quartz glass is used for the diffractive optical element. In the manufacturing method of the optical disc original disk of any one of Claims 1-3,
A method of manufacturing an optical disc master, wherein a phase change medium is used as a resist in the exposure step, and only a region having a desired energy density or higher is developed by the recording beam spot. In the manufacturing method of the optical disk original disk of any one of Claims 1-4,
The method of manufacturing an optical disc master, wherein the diffractive optical element transforms incident light from the exposure light source into a uniform distribution within the condenser lens pupil and to an intensity distribution with extremely low brightness otherwise. In the manufacturing method of the optical disk original disk of any one of Claims 1-4,
The method of manufacturing an optical disc master, wherein the diffractive optical element transforms incident light from the exposure light source into an intensity distribution that forms a ring within the condenser lens pupil.   An optical disc manufacturing method, wherein an optical disc is manufactured using the optical disc master manufactured by the method of manufacturing an optical disc master according to any one of claims 1 to 6. An exposure apparatus for performing exposure for recording reproduction information on an optical disc master,
An exposure light source that emits laser light;
A diffractive optical element that is provided in the optical path of the exposure light source and forms a laser beam emitted from the exposure light source into a light beam having a desired shape;
A condenser lens that forms the light beam formed by the diffractive optical element into the shape of a recording beam spot;
The diffractive optical element is an exposure apparatus characterized in that the laser beam emitted from the exposure light source is formed into a shape in which a recording beam spot formed by the condenser lens is sharpened and the spot diameter is reduced. An exposure apparatus for performing exposure for recording reproduction information on an optical disc master,
An exposure light source that emits laser light;
A diffractive optical element that is provided in the optical path of the exposure light source and forms a laser beam emitted from the exposure light source into a light beam having a desired shape;
A condenser lens that forms the light beam formed by the diffractive optical element into the shape of a recording beam spot;
The diffractive optical element forms the laser beam emitted from the exposure light source into a shape that improves the center intensity of a recording beam spot formed by the condenser lens. The exposure apparatus according to claim 8 or 9,
The exposure apparatus is characterized in that the exposure light source irradiates laser light made of ultraviolet light having a wavelength of 300 nm or less, and the diffractive optical element is made of quartz glass. In the exposure apparatus according to any one of claims 8 to 10,
The resist exposed by the recording beam spot formed by the condensing lens is made of a phase change medium, and develops only the region having a desired energy density or higher by the recording beam spot of the condensing lens. An exposure apparatus. In the exposure apparatus according to any one of claims 8 to 11,
The diffractive optical element transforms incident light from the exposure light source into a uniform distribution in the condenser lens pupil, and to an intensity distribution that has extremely low brightness otherwise. In the exposure apparatus according to any one of claims 8 to 11,
The diffractive optical element transforms incident light from the exposure light source into an intensity distribution that forms a ring within the condenser lens pupil.

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